Management of sodium-channel blocker poisoning: the role of hypertonic sodium salts.

Sodium-channel blockers act by slowing sodium influx into myocytes through voltage gated channels. Many substances have sodium-channel blocking properties and many others show this effect when taken in overdose. Sodium-channel blocker poisoning, associated with a high death rate, is characterized by a variety of clinical presentation, depending on the pharmaceutical agent involved. Sodium bicarbonate or lactate, increasing serum pH and extracellular concentration of the ion, displace the drug from its receptor sites and can be used for the treatment of cardiac toxicity in the setting of sodium-channel blocker poisoning. In spite of this theoretical assumption, the role played by hypertonic sodium salts is not well elucidated and conflicting results have been reported. Authors review the pathophysiologic mechanisms of sodium-channel blocker poisoning and the evidences in literature concerning the efficacy of hypertonic sodium salts in the treatment of the related toxicity.

Neutrophil gelatinase-associated lipocalin: a novel biomarker for the early diagnosis of acute kidney injury in the emergency department.

Acute kidney injury (AKI) is a common medical problem among critical patients. In current clinical practice, AKI is diagnosed by measuring serum creatinine concentration, which is an unreliable and delayed marker of the deterioration of kidney function. Its rise occurs when a significant amount of renal function has been lost. Many are the factors able to modify physiological levels, such as age, gender, ethnicity, dietary protein intake, muscle mass or metabolism, hydration status and drugs. Definitely, creatinine, as well as blood urea nitrogen (BUN) or urine markers of kidney injury (fractional excretion of sodium, urinary concentrating ability, casts), do not directly reflect cell injury, but rather the delayed functional consequences of the damage. Due to the lack of sensitive and specific biomarkers, the identification of early stages of AKI has been impossible but, recently, neutrophil gelatinase-associated lipocalin (NGAL) is emerging as a novel biomarker of AKI from several etiologies, such as cardiac surgery, contrast nephropathy, kidney transplantation and sepsis. This protein, produced in a number of human tissues and particularly in the distal nephron, has siderophore-chelating property and acts as an iron-trasporting shuttle. NGAL increases in both serum and urine 48 hours before the rise of creatinine, and shows a strong correlation with change in creatinine concentrations. An early diagnosis of AKI allows the early institution of therapeutic measures for the protection of renal function and improves the prognosis. This possibility is particularly important in the Emergency Department for the treatment of critical patients with potential nefrotoxic therapies. Use of NGAL as early marker of AKI in the Emergency Department is discussed.

Hypokalemic rhabdomyolysis in a patient with a laparoscopic adjustable gastric banding.

Rhabdomyolysis is an acute skeletal muscle disorder characterized by altered integrity of the cell membranes of muscle fiber cells. It can be related to a variety of factors: muscular trauma, muscle enzyme deficiencies, infections, drugs, toxins, alcohol ingestion, endocrinopathies and electrolyte imbalances such as hypokalemia. We report the case of a 46-year-old woman admitted to the Emergency Department for frequent episodes of vomiting associated with food intake in the last two weeks, general muscular weakness and myalgia. Physical examination on admission was unremarkable, except for a symmetrical and dominantly proximal muscular weakness of all four extremities. Blood pressure was 116/70 mmHg with a sinus bradycardia (53 beats/min) on the electrocardiogram. Laboratory tests showed a metabolic alkalosis with marked hypokalemia (K+= 1.9 mEq/l) and elevation of muscular enzymes (myglobin= 993 ng/ml, troponin T= 0,10 ng/ml e CK= 1113 U/l). No symptoms of recurrent rhabdomyolysis were reported, patient denied alcohol consumption and there was not clinical evidence of hyperthyroidism. A iatrogenic etiology could not be excluded for certain because patient was in therapy with lansoprazole (Naranjo algorithm 3/13) but, revealing medical history that she underwent a laparoscopic adjustable gastric banding for the treatment of a severe obesity, we focused our attention on hypokalemia, due to persistent vomiting. Fasting, administration of metoclopramide and infusion of potassium chloride resulted in steady improvement of clinical conditions and normalization of electrolyte imbalance. At the clinical follow-up of three months, after partial deflation of the gastric banding, the patient was asymptomatic with muscular enzymes and potassium levels in the normal range. Authors discuss the pathophysiologic mechanisms of these alterations.

Metformin-induced lactic acidosis in a type 2 diabetic patient with acute renal failure.

Metformin is a biguanide commonly used in type 2 diabetes mellitus (DM). Lactic acidosis, a potentially life-threatening metabolic disorder, may be due to a number of different causes, including metformin therapy. We present a case of a severe metformin-induced lactic acidosis in a patient with type 2 DM, admitted to the emergency department with a history of dehydration due to diarrhoea and complicated by acute renal failure. Patient complained malaise and severe weakness and was tachypneic (Kussmaul's respiration), agitated and confused, with a Glasgow Coma Scale score of 13/15. Heart rate was 75 b/min and blood pressure 110/80 mmHg. The pH was 6.87, HCO3- 3 mmol/l, lactate 15 mmol/l, potassium 6.9 mEq/l. The renal function was markedly impaired with a creatinine of 9.75 mg/dl, and pancreatic enzymes, amylase and lipase, were also increased in absence of abdominal pain. Patient was treated with intravenous fluids, bicarbonate infusion and haemodialysis with bicarbonate buffered replacement fluid. Clinical conditions improved rapidly, with a progressive normalization of the acid-base balance and the other laboratory data. Authors discuss the pathophysiologic mechanisms of these alterations with particular regard to the role played by metformin as potential cause of lactic acidosis.

Differential transfer benefits of increased practice for constant, blocked, and serial practice schedules.

The effects of practice schedule and amount of practice on the development of the generalized motor program (GMP) and on parameter estimation were investigated. Participants (N = 108) practiced the same relative timing but different absolute durations of a multisegment timing task. Practice schedules (constant, blocked, or serial) were crossed with amounts of practice (low and high). Inclusion of a constant practice condition allowed the authors to investigate the variability of practice prediction. Participants practiced the same proportional durations in a serial or a blocked schedule, which enabled the authors to examine contextual interference. A constant practice schedule enhanced GMP performance when task parameters remained the same, but varied practice schedules were beneficial when task parameters changed. A serial as opposed to a blocked practice schedule was superior when the performance of a task governed by a different GMP was required. Increased practice led to a consolidated task representation that was unavailable for updating.

Comparison of measures of physiologic stress during treadmill exercise in a patient with 20% lower extremity burn injuries and healthy matched and nonmatched individuals.

Patients with burn injuries are referred for rehabilitation within days after the injuries to encourage early ambulation and functional training. Many of these patients are hypermetabolic at rest. Metabolic demands of activity are added to the already hypermetabolic state and elevate total energy requirements and some physiologic measures. Reports on the physiologic stress imposed by therapeutic activities for patients with burn injuries are limited to low levels of metabolic demand (< or =2 metabolic equivalents [METS]). The degree of stress imposed by functional activities such as ambulation (3 METS) and stair climbing (5 METS) is not known for adults with burn injuries. The purpose of this study was to report the clinical measures of myocardial and physiologic stress in a patient with 20% lower extremity total body surface area burns during an exercise challenge equivalent to stair climbing. Physiologic measures were assessed before and during a treadmill activity (5 METS) for a 40-year-old obese man 3 weeks after he had lower extremity burn injuries. These measures were compared with mean values for 62 healthy counterparts and 6 healthy subjects matched for age, gender, and fitness level. Heart rate, systolic blood pressure, rate pressure product, and the rating of perceived exertion for the patient with burn injuries were higher at baseline and during exercise than the mean values for the 62 healthy individuals and the 6 matched subjects. The steady state exercise values for heart rate, systolic blood pressure, rate pressure product, and rating of perceived exertion at 6 minutes were 189 beats per minute, 190 mm Hg, 3591, and 17, respectively, for the patient with burn injuries and were 111.3 beats per minute, 149 mm Hg, 1680, and 11.7, respectively, for the 6 matched subjects. Ventilation during exercise also increased for the patient with burn injuries more than for the matched subjects (3/4 vs 1/4). Pain experienced by the patient with burn injuries decreased with activity (9.8 vs 7.3 on a 15-cm scale). Treadmill walking produced near maximal responses for most physiologic measures for this patient who was hypermetabolic at rest. We provided normative data to assist therapists who work with patients with similar burn injuries.

[The scombroid syndrome, a potentially serious ichthyotoxicosis of uncertain pathogenesis: personal experience]. / Sindrome sgombroide, una ittiotossicosi a patogenesi incerta potenzialmente grave: esperienza personale.

The aim of this report is to point out the potential seriousness of the scombroid syndrome which, on the basis of our experience, can be characterized by extremely serious symptoms. We describe 12 cases of scombroid syndrome: two-thirds of the patients presented with rapid worsening of their clinical condition and hypotension severe enough to require use of plasma-expanders and hospitalization in an Internal Medicine Department. In the youngest patient, hypotension and symptoms were so marked that intravenous administration of epinephrine, and hospitalization in the Intensive Care Unit were required. Thus, in contrast to reports in the literature, the scombroid syndrome should be considered as a potentially serious ichthyotoxicosis. The pathogenetic role played by histamine, poorly absorbed by the intestine and rapidly metabolized by the liver, should be reevaluated. The potential onset of serious clinical symptoms warrants prolonged observation of the patient in an environment equipped to deal with the not infrequent emergencies that can arise, even in young and healthy subjects.

Invasive aspergillosis in neutropenic patients: rapid neutrophil recovery is a risk factor for severe pulmonary complications.

BACKGROUND: In invasive aspergillosis, the duration of neutropenia is an accepted risk factor, and recovery from neutropenia is generally associated with a favourable outcome. However, the rapidity of granulocyte recovery may rarely be associated with adverse sequelae. The purpose of this study was to define the relationship between neutrophil (polymorphonuclear, PMN) recovery after chemotherapy-induced bone marrow aplasia and the occurrence of severe pulmonary complications (haemoptysis, pneumothorax and death) in patients with haematological malignancies who developed invasive fungal pneumonias. METHODS: Twenty consecutive patients were retrospectively studied; eight of them had developed pulmonary events between 5 and 11 days after neutrophil recovery that followed deep neutropenia (PMN < 100 microL-1). RESULTS: Five patients had haemoptysis (one of these also had pneumothorax) and three had pneumothorax. According to the multiplicative logistic model, the odds of occurrence of a pulmonary event increased significantly with increasing PMN count on the fifth day (P < 0.001). Five of the eight patients who had pulmonary complications died. Also, the risk of death was larger in the presence of rapid neutrophil recovery, although the difference was not statistically significant (P = 0.111). Analysis of clinical and laboratory data showed that the risk of pulmonary complications significantly increased when the neutrophil concentration was > 4500 microL-1 on day 5 after deep granulocyte neutropenia (PMN < 100 microL-1). There was no correlation between pulmonary complications, dosage of amphotericin B and deaths. CONCLUSION: The occurrence of life-threatening complications in patients with invasive fungal pneumonia is closely related to rapid PMN recovery.

Neuroradiologic picture of cerebral vasculitis in rheumatoid arthritis.

The central nervous system is rarely involved in rheumatoid arthritis. In this paper the authors report a case of a 50-year-old woman who had rheumatoid arthritis for about 6 years. A month before admission she presented a symptomatology resembling an expansive intracranial process. Angiography revealed cerebral arteritis and CT showed areas of hypodensity with marked contrast enhancement.